A7r 24-70 at 70mm vs EM1 12-40 at 40mm (80mm EFL)

You showed the extreme, but to be completely correct, you need to crop the A7R image to 4/3. This is what the E-M1 + 12-40 is doing after all. Then you can resize them and do the comparison. The Olympus combo would look even worst then.

I'm glad I came by this thread, because I ordered this lens prior to coming across this thread.